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Hi all,<br><br>
My question is regarding to a particular implementation of a Registration
algorithm I have just tried without success.<br>
Firstly I checked the example
"<font face="Arial, Helvetica" color="#008000">
ImageRegistration8.cxx</font>", in which the use of the
"<font face="Arial, Helvetica" color="#800000">
itkVersorRigid3DTransform</font>" is illustrated, and it
worked.<br>
Then I did the same with the example
"<font face="Arial, Helvetica" color="#008000">
ImageRegistrationHistogramPlotter.cxx</font>", which deals with the
"<font face="Arial, Helvetica" color="#008000">
MutualInformationHistogramImageToImageMetric</font>", and also
worked properly with my images. (Since they are 3D volumes I did the
required changes and I had no problems at all).<br><br>
However, when I tried to create a new algorithm with the
elements:<br><br>
TRANSFORM:
<font face="Arial, Helvetica" color="#800000">itkVersorRigid3DTransform
(with the itkCenteredTransformInitializer)<br>
</font>OPTIMIZER:
<font face="Arial, Helvetica" color="#800000">
itkVersorRigid3DTransformOptimizer<br>
</font>METRIC:
<font face="Arial, Helvetica" color="#008000">
MutualInformationHistogramImageToImageMetric<br>
</font>INTERPOLATOR:
<font face="Arial, Helvetica" color="#800000">
itkLinearInterpolateImageFunction<br><br>
</font>The code was properly built but I achieved a permanent error in
execution:<br><br>
<i>ExceptionObject caught !<br><br>
itk::ExceptionObject (013CF7FC)<br>
Location: "void __thiscall itk::HistogramImageToImageMetric<class
itk::Image<float,3>,class itk::Image<float,3>
>::ComputeHistogram(const class itk::Array<double> &,class
itk::Statistics::Histogram<double,2,class
itk::Statistics::DenseFrequencyContainer> &) const" <br>
File:
c:\itk\insighttoolkit-3.2.0\code\algorithms\itkHistogramImageToImageMetric.txx<br>
Line: 303<br>
Description: itk::ERROR:
MutualInformationHistogramImageToImageMetric(018A50D8): All the points
mapped to outside of the moving image<br><br>
</i>I guessed that the problem came from the initialization of the
Optimizer: <br><br>
<font face="Arial, Helvetica">
</font><font face="Arial, Helvetica" color="#0000FF"><i>typedef</font>
<font face="Arial, Helvetica">
OptimizerType::ScalesType
OptimizerScalesType;<br>
OptimizerScalesType optimizerScales(
transform->GetNumberOfParameters() );<br>
</font><font face="Arial, Helvetica" color="#0000FF">const</font>
<font face="Arial, Helvetica">
</font><font face="Arial, Helvetica" color="#0000FF">double</font>
<font face="Arial, Helvetica"> translationScale = 1.0 / 1000.0;<br><br>
optimizerScales[0] = 1.0;<br>
optimizerScales[1] = 1.0;<br>
optimizerScales[2] = 1.0;<br>
optimizerScales[3] = translationScale;<br>
optimizerScales[4] = translationScale;<br>
optimizerScales[5] = translationScale;<br><br>
optimizer->SetScales( optimizerScales );<br><br>
optimizer->SetMaximumStepLength( 0.2000 ); <br>
optimizer->SetMinimumStepLength( 0.0001 );<br><br>
optimizer->SetNumberOfIterations( 200 );<br><br>
<br>
</i></font>but I was playing with it and I couldn't avoid the fail... The
same with the initialization of the transform:<br><br>
<font face="Arial, Helvetica"><i> </font>
<font face="Arial, Helvetica" color="#0000FF">typedef</font>
<font face="Arial, Helvetica"> itk::CenteredTransformInitializer<
TransformType, <br>
FixedImageType, <br>
MovingImageType <br>
> TransformInitializerType;<br><br>
TransformInitializerType::Pointer initializer = <br>
TransformInitializerType::New();<br>
</font>(</i>...)<br><br>
I have tried it with different images (different sizes and resolution).
All of them are MRI dynamic studies of the abdominal region (3D volumes
on time). I'd really like to know what's happening with my piece of code.
<b>Is there any specific limitation for mixing those elements in a new
algorithm?<br><br>
</b>Thank you very much in advance.<br>
Rosario<br>
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<font face="Eras Medium ITC">
___________________________________________________</font> <br><br>
<font face="Arial TUR, Helvetica">Rosario Sance Garzón<br>
Grupo de Tecnologías de Imagen Biomédica<br>
Dpto. Ingeniería Electrónica<br>
E.T.S.I. Telecomunicación - UPM<br>
Ciudad Universitaria<br>
28040 - Madrid <br><br>
</font>Teléfono: 91 549 57 00 (Ext. 4220) <br>
Fax: 91 336 73 23<br>
Web:
<a href="http://www.die.upm.es/im" eudora="autourl">
http://www.die.upm.es/im<br>
</a><font face="Eras Medium ITC">
___________________________________________________</font> <br><br>
<font face="Arial TUR, Helvetica"><i>Rosario Sance Garzón<br>
Biomedical Image Techologies<br>
Electronic Engineering Department<br>
E.T.S.I. Telecomunicación - UPM<br>
Ciudad Universitaria<br>
E-28040 - Madrid (SPAIN)<br><br>
</font>Telephone: +34 91 549 57 00 (Ext. 4220) <br>
Fax: +34 91 336 73 23<br>
Web:
<a href="http://www.die.upm.es/im" eudora="autourl">
http://www.die.upm.es/im<br>
</a></i><font face="Eras Medium ITC">
___________________________________________________</font> <br>
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